JP5761771B2 - Wafer map data verification system - Google Patents

Description

The present invention is an invention concerning the wafer map data matching system for matching the wafer image and the wafer map data image.

  In general, a wafer is bonded to a dicing sheet, diced, and divided into a large number of dies (semiconductor chips). Since one wafer contains defective dies, the die inspection process inspects the quality of each die, attaches a bad mark with ink to the defective dies, and the die mounting process images each die with a camera. Then, the presence / absence of a bad mark is image-recognized, and only good dies (good chips) are picked up sequentially from the wafer and mounted on the substrate.

  However, this method has a drawback in that the production efficiency is poor because each die must be imaged with a camera to recognize the presence or absence of bad marks.

  Therefore, in recent years, as described in Patent Document 1 (Japanese Patent Laid-Open No. 2001-250834), in the die inspection process, wafer map data indicating the quality of the dies at each position of the wafer after dicing is created, In the die mounting process, a method of picking up only non-defective dies (non-defective chips) from the wafer in order using the wafer map data and mounting them on the substrate has become mainstream.

  In this method, it is necessary to collate the actual wafer with the wafer map data, and to accurately correspond the quality of the die at each position of the actual wafer with the wafer map data.

  Therefore, as described in Patent Document 2 (Japanese Patent Laid-Open No. 2008-31430), a technique for automatically matching an actual wafer and wafer map data using a pattern matching technique has been proposed. . In this device, a camera and an illumination light source are arranged on opposite sides of a dicing sheet with a wafer attached thereto, and an image is taken by illuminating with an illumination light source from the back side of the wafer (dicing sheet) when viewed from the camera side. This facilitates image recognition of each die on the wafer.

JP 2001-250834 A JP 2008-31430 A JP 2010-129949 A

  However, in the above-mentioned Patent Document 2, the camera and the illumination light source are arranged opposite to each other with the dicing sheet interposed therebetween, but the dicing sheet adsorbed below the dicing sheet of the die pickup device is picked up. Since it is necessary to arrange a push-up mechanism that pushes up the sticking part of the die to be pushed up with a push-up pin and partially peels off the sticking part of the die from the dicing sheet, an illumination light source (or camera) is provided below the dicing sheet. ) Is difficult to arrange (see Patent Document 3).

In addition, since the die is small and small, it is easily affected by manufacturing variations, and it is difficult to accurately recognize the die on the peripheral edge of the wafer. For this reason, even if the method of Patent Document 2 is used, it is difficult to automatically collate an actual wafer and wafer map data, and there is a possibility that the position of the die is erroneously recognized.

  For this reason, at present, the actual wafer image and the wafer map data image are displayed side by side on the screen of the display device, and the operator visually checks the actual wafer image and the wafer map data image to determine the suction start die. Although it is specified, since the wafer map data image image is different from the actual wafer image, the collation work requires skill, and if a less skilled worker performs the collation work, the position of the die will shift. May be collated. If the matching position of the die is shifted, picking up the die according to the wafer map data will pick up the die while shifting the position of the non-defective / defective product, resulting in a defective substrate. It will be.

Therefore, an object of the present invention is to provide provide a wafer map data matching systems that can be easily and accurately matching operator visually actual wafer image and the wafer map data image displayed on the screen of the display device That is.

  In order to solve the above-described problems, the present invention provides a wafer image obtained by imaging at least a part of a wafer diced so as to be divided into a plurality of dies, and wafer map data indicating the quality of the dies at each position of the wafer. In a wafer map data collation system, comprising: a display device that displays an image; and an operation unit that performs an operation of collating the wafer image and the wafer map data image. The wafer map data image is the same as the wafer image. Displayed as an array image of dies, and the operation means moves the display position of the wafer image or the wafer map data image on the screen of the display device to superimpose the wafer image and the wafer map data image. By matching, the wafer image and the wafer map data image are collated. It is characterized in.

  In this configuration, the display position of the wafer image or wafer map data image is moved on the screen of the display device, and the wafer image and the wafer map data image are overlapped and matched to thereby match the wafer image and the wafer map data image. Since the collation can be performed, the operator can easily and accurately collate the actual wafer image displayed on the screen of the display device and the wafer map data image visually.

  The operator may operate the operation means and designate the suction start die in a state where the wafer image and the wafer map data image are overlapped and matched. As a result, the operator can easily and accurately specify the suction start die visually.

  Further, in the wafer map data image, a portion without a die and a portion with a die may be divided by different backgrounds (color display, gray display, pattern, etc.). Thus, the operator can easily and accurately determine the die at the peripheral edge of the wafer displayed in the wafer map data image.

  In addition, the wafer map data image may be displayed with marks (symbols, characters, marks, color display, gray display, etc.) on the defective die sections. Thereby, the operator can easily visually confirm the position of the defective die on the screen of the display device. Also, if a bad mark is attached to the defective die on the wafer, it is easy to visually confirm that the bad mark position on the wafer image matches the defective die mark position on the wafer map data image. Can do.

FIG. 1 is an external perspective view of a die supply apparatus according to an embodiment of the present invention. FIG. 2 is an external perspective view of the push-up unit and its peripheral part. FIG. 3 is an external perspective view of the wafer pallet. FIG. 4 is a partially broken enlarged view showing a state in which the push-up pot is raised to the suction position during the push-up operation. FIG. 5 is a partially broken enlarged view showing a state in which the push-up pin is protruded from the push-up pot during the push-up operation. FIG. 6 shows an example of wafer map data. FIG. 7A shows an example of a wafer image, and FIG. 7B shows an example of a wafer map data image. FIG. 8A is a diagram showing a state in the middle of the image overlay operation, and FIG. 8B is a diagram showing a state in which the image overlay operation is completed.

Hereinafter, an embodiment embodying a mode for carrying out the present invention will be described.
First, the structure of the die pick-up apparatus 11 is demonstrated roughly using FIG.

  The die pick-up device 11 includes a magazine holding unit 22 (tray tower), a pallet drawer table 23, an XY moving mechanism 25, a push-up unit 28 (see FIG. 2), and the like, and the pallet drawer table 23 is a component mounter (not shown). Is set to the state where it is plugged in.

  In a magazine (not shown) housed in a magazine holding portion 22 of the die pick-up device 11 so as to be movable up and down, wafer pallets 32 equipped with wafer extending bodies 30 are stacked in multiple stages. The pallet 32 is pulled out on the pallet drawer table 23. As shown in FIG. 3, the wafer extending body 30 is formed by attaching an expandable / shrinkable dicing sheet 34 with a die 31 formed by dicing the wafer into a grid pattern on a wafer mounting plate 33 having a circular opening. The wafer mounting plate 33 is mounted in an expanded state, and the wafer mounting plate 33 is attached to the pallet main body 35 by screws or the like.

  The push-up unit 28 (see FIG. 2) is configured to be able to move in the XY direction in a space area below the dicing sheet 34 of the wafer pallet 32. And the sticking part of the die 31 to be picked up (sucked) in the dicing sheet 34 is pushed up from below and pushed up locally by a push-up pin 39 (see FIGS. 4 and 5) of the pot 37, so that the die The sticking part of 31 is partly peeled off from the dicing sheet 34 so that the die 31 can be easily lifted.

The push-up unit 28 is configured such that the push-up unit 28 as a whole moves up and down using a servo motor (not shown) as a drive source. During the die pick-up operation, when the push-up unit 28 is raised and the upper surface of the push-up pot 37 rises to a predetermined sheet suction position where it substantially contacts the dicing sheet 34 of the wafer pallet 32, the stopper unit (not shown) When the ascent is stopped and the ascending operation is continued, the push-up pin 39 (see FIGS. 4 and 5) protrudes upward from the upper surface of the push-up pot 37, and the sticking portion of the die 31 to be picked up in the dicing sheet 34 To come up. In this case, the push-up height position (push-up amount) of the push-up pin 39 can be adjusted by adjusting the rotation amount of the servo motor serving as the drive source.

  As shown in FIG. 1, the suction head 41 and the camera 42 are assembled to the XY movement mechanism 25, and the suction head 41 and the camera 42 are integrally moved in the XY directions by the XY movement mechanism 25. ing. The suction head 41 is provided with a suction nozzle 43 (see FIGS. 4 and 5) that sucks the die 31 on the dicing sheet 34 so as to move up and down. The camera 42 can recognize the position of the die 31 to be sucked by the suction nozzle 43 by picking up an image of the die 31 on the dicing sheet 34 from above and processing the picked-up image.

  A control device (not shown) of the die pick-up device 11 processes an image obtained by picking up the die 31 to be attracted by the camera 42 out of the dies 31 on the dicing sheet 34 and positions the die 31. , The push-up position and suction position of the die 31 are determined, and the sticking portion of the die 31 to be picked up (sucked) out of the dicing sheet 34 is pushed up from below as shown in FIG. The sticking portion of the die 31 is lifted locally by the push-up pins 39 of the die 37 so that the die 31 is lifted to a state where it can be easily picked up by partially peeling the die 31 from the dicing sheet 34. Adsorb and pick up.

  In general, since a defective wafer is included in one wafer, a wafer manufacturer / manufacturer manufactures wafer map data (figure) indicating the quality of the die 31 at each position of the wafer after dicing based on the die inspection result. 6) and provide the wafer map data together with the wafer to the die mounting board manufacturing company. A die mounting board manufacturing company uses the die pick-up device 11 to sequentially pick up only non-defective dies (non-defective chips) from the wafer according to the wafer map data and mount them on the substrate.

  As described above, when using the wafer map data, it is necessary to collate the actual wafer with the wafer map data and to accurately correspond the quality of the die at each position of the actual wafer with the wafer map data.

  Therefore, in this embodiment, as shown in FIG. 7, the actual wafer image and wafer map data image captured by the camera 42 are displayed on the screen of a display device (not shown), and both images are displayed as follows. To verify.

  In this embodiment, the bad die of the wafer is marked with a bad mark with ink so that the operator can visually confirm the defective die. However, the defective die is not marked with a bad mark. Also good.

  Further, the wafer map data image is the same die array image as the wafer image, and the sections of each die partitioned by grid-like lines are displayed in the same size as each die of the wafer image. In addition, the wafer map data image is divided into different backgrounds (color display, gray display, pattern, etc.) where there are no dies and where there are dies, and the peripheral dies on the wafer displayed in the wafer map data image are displayed. An operator can easily and accurately discriminate visually.

  In addition, the wafer map data image has marks (symbols, characters, marks, color display, gray display, etc.) displayed on the defective die sections, and the operator can easily visually check the position of the defective die on the display device screen. It can be confirmed.

The operation of collating the actual wafer image displayed on the screen of the display device with the wafer map data image is performed by an operator operating an input device (operation means) such as a mouse or a keyboard, or the screen of the display device is In the case of a touch panel (operation means), the operator touches the screen of the display device with a finger or the like, and the wafer image or wafer map data is displayed on the screen of the display device as shown in FIG. As shown in FIG. 8B, the display position of the image is moved and overlapped so that each die of the wafer image and each die section of the wafer map data image are matched. In this embodiment, since a bad mark in the wafer is marked with a bad mark, it is easy to visually confirm that the position of the bad mark in the wafer image matches the position of the defective die in the wafer map data image. Can be confirmed.

  As described above, in a state where the wafer image and the wafer map data image are overlapped and matched, the operator operates the input device such as a mouse or a keyboard or the touch panel to designate the suction start die. Thereafter, production is started, and only good dies are picked up in order from the suction start die according to the wafer map data and mounted on the substrate.

  According to the present embodiment described above, an operator operates an input device such as a mouse or a touch panel to move the display position of the wafer image or the wafer map data image on the screen of the display device, so that the wafer image and the wafer are moved. By overlapping and matching the map data image, the wafer image and the wafer map data image can be collated, so that the operator can visually check the actual wafer image and the wafer map data image displayed on the display device screen. Thus, it is possible to easily and accurately collate, and the operator can easily and accurately designate the suction start die visually. Thereby, the workability of collation work is good and the setup time can be shortened. In addition, since the operator can easily and accurately specify the suction start die by visual observation, it is possible to prevent erroneous suction of the defective die and to prevent the production of defective substrates.

  In this embodiment, the image of the entire wafer and the entire image of the wafer map data are displayed on the screen of the display device. However, if the field of view of the camera 42 is narrow and only a part of the wafer can be imaged, the display device A part of the wafer image captured by the camera 42 is displayed on the screen, and a part of the wafer map data corresponding to the display part is displayed, and one of the images is moved to superimpose both images. By matching them together, the wafer image and the wafer map data image may be collated.

  In addition, it has a function to adjust the display magnification of the wafer image and wafer map data image displayed on the screen of the display device, and the display magnification of the wafer image and wafer map data image can be adjusted on the screen of the display device by the operator's operation. It may be possible to adjust.

  The die pickup apparatus 11 of the present embodiment is configured such that the suction head 41 and the camera 42 are integrally moved in the XY direction by the XY moving mechanism 25. However, the suction head 41 and the camera 42 are moved only in the X direction. In addition, the wafer pallet 32 may be moved in the Y direction on the pallet drawer table 23 so that the position of the die 31 to be imaged / sucked moves in the XY direction.

  In addition, it goes without saying that the present invention can be implemented with various modifications within a range not departing from the gist, such as appropriately changing the configuration of the die pickup device 11 and the configuration of the wafer pallet 32.

  DESCRIPTION OF SYMBOLS 11 ... Die pick-up apparatus, 22 ... Magazine holding part, 23 ... Pallet drawer table, 25 ... XY movement mechanism, 28 ... Push-up unit, 30 ... Wafer extension body, 31 ... Die, 32 ... Wafer pallet, 33 ... Wafer mounting plate 34 ... Dicing sheet, 37 ... Push-up pot, 39 ... Push-up pin, 41 ... Suction head, 42 ... Camera, 43 ... Suction nozzle

Claims (4)

A display device for displaying a wafer image obtained by imaging at least a part of a wafer diced so as to be divided into a plurality of dies, and a wafer map data image indicating the quality of the die at each position of the wafer; and the wafer image And a wafer map data collation system comprising operation means for performing an operation of collating the wafer map data image with the wafer map data image,
The wafer map data image is displayed in the same die array image as the wafer image,
The operation means moves the display position of the wafer image or the wafer map data image on the screen of the display device to superimpose the wafer image and the wafer map data image so as to match the wafer image. And a wafer map data image, wherein the wafer map data verification system is configured to verify the wafer map data image.   2. The wafer map data collating system according to claim 1, wherein the operation means includes means for designating a suction start die in a state where the wafer image and the wafer map data image are overlapped and matched.   3. The wafer map data collating system according to claim 1, wherein the wafer map data image includes a background without a die and a portion with a die separated by different backgrounds.   4. The wafer map data collating system according to claim 1, wherein a mark is displayed on a defective die section in the wafer map data image.

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